Chapter 6 PHP Directory and File Operation_PHP Tutorial
one. Directory operations
basename -- Returns the file name part of the path
dirname -- Returns the directory part of the path
pathinfo -- Returns file path information
realpath -- Returns the normalized absolute path name
$path = 'demo1.php';
$path = realpath($path);
echo basename($path);
echo '
';
echo dirname($path);
echo '
';
$array_path = pathinfo($path);
echo 'basename : '.$array_path['basename'].'
';
echo 'dirname : '.$array_path[ 'dirname'].'
';
echo 'extension : '.$array_path['extension'].'
';
echo 'filename : '.$array_path['filename '].'
';
?>
Output:
demo1.php
D:AppServwwwBasic6
basename : demo1.php
dirname: D:AppServwwwBasic6
extension: php
filename: demo1
2. Disk, directory and file count
1. View file size and disk space
filesize -- Get the file size
disk_free_space -- Return the available space in the directory
disk_total_space -- Return the total disk space of a directory Size
$path ='demo2.php';
$path = realpath($path);
$drive = 'c:';
echo round(filesize($path)/1024,2).'kb'.'
';
echo round(disk_free_space($drive)/1024/1024/1024,2).'GB'.'
';
echo round(disk_total_space($drive)/1024/ 1024/1024,2).'GB'.'
';
?>
output
0.26kb
10.61GB
30.01 GB
2. Get various times of files
fileatime -- Get the last access time of the file
filectime -- Get the inode modification time of the file
filemtime -- Get the file modification time
$file = realpath ( '../Basic5/ demo3.php' );
$date_format = 'Y-m-d h:i:s';
echo 'lastest accessing time : '.date ( $date_format, fileatime ( $file ) ) . '
' ;
echo 'lastest change time : '.date ( $date_format, filectime ( $file ) ) . '
';
echo 'lastest modify time : '.date ( $date_format, filemtime ( $ file ) ) . '
';
?>
output
lastest accessing time : 2011-12-18 04:26:49
lastest change time : 2011-12-18 04:26:49
lastest modify time : 2011-12-18 04:29:15
三.文件处理
文件读写的两种方式:
1.php所有版本都支持的方法:
fopen -- 打开文件或者 URL
fclose -- 关闭一个已打开的文件指针
fwrite -- 写入文件(可安全用于二进制文件)
表 1. fopen() 中 mode 的可能值列表
mode |
说明 |
'r' |
只读方式打开,将文件指针指向文件头。 |
'r+' |
读写方式打开,将文件指针指向文件头。 |
'w' |
写入方式打开,将文件指针指向文件头并将文件大小截为零。如果文件不存在则尝试创建之。 |
'w+' |
读写方式打开,将文件指针指向文件头并将文件大小截为零。如果文件不存在则尝试创建之。 |
'a' |
写入方式打开,将文件指针指向文件末尾。如果文件不存在则尝试创建之。 |
'a+' |
读写方式打开,将文件指针指向文件末尾。如果文件不存在则尝试创建之。 |
'x' |
创建并以写入方式打开,将文件指针指向文件头。如果文件已存在,则 fopen() 调用失败并返回 FALSE,并生成一条 E_WARNING 级别的错误信息。如果文件不存在则尝试创建之。这和给 底层的 open(2) 系统调用指定 O_EXCL|O_CREAT 标记是等价的。此选项被 PHP 4.3.2 以及以后的版本所支持,仅能用于本地文件。 |
'x+' |
创建并以读写方式打开,将文件指针指向文件头。如果文件已存在,则 fopen() 调用失败并返回 FALSE,并生成一条 E_WARNING 级别的错误信息。如果文件不存在则尝试创建之。这和给 底层的 open(2) 系统调用指定 O_EXCL|O_CREAT 标记是等价的。此选项被 PHP 4.3.2 以及以后的版本所支持,仅能用于本地文件。 |
$fp = fopen('file1.txt','w');
$outStr = "my name is anllin,\r\nmy age is 29.";
fwrite($fp,$outStr,strlen($outStr));
fclose($fp);
?>
output
my name is anllin,
my age is 29.
2.php5新加入的方法
file_put_contents -- 将一个字符串写入文件
file_put_contents('file2.txt',"my name is anllin,\r\nmy age is 29.");
?>
output
my name is anllin,
my age is 29.
读出文件内容的方法:
函数 |
功能 |
Fgetc() |
读出一个字符,并将指针移到下一个字符 |
Fgets() |
读出一行字符,可以指定一行显示的长度。 |
Fgetss() |
从文件指针中读取一行并过滤掉HTML标记 |
Fread() |
读取定量的字符 |
Fpassthru() |
输出文件到指定处的所有剩余数据 |
File() |
将整个文件读入数组中,以行分组 |
Readfile() |
读入一个文件并写入到输出缓冲 |
File_get_contents() |
将整个文件读入一个字符串 |
Feof() |
判断读完文件函数 |
File_exists() |
查看文件是否存在 |
my name is anllin,
my age is 29.
fgetc -- Read characters from the file pointer
Demo.php
$fp = fopen('file1.txt','r');
echo fgetc($fp);
echo fgetc($fp);
fclose($fp);
?>
Output:
my
fgets -- Read a line from the file pointer
$fp = fopen('file1.txt','r');
echo fgets($fp);
echo fgets($fp);
fclose($fp);
? >
output
my name is anllin, my age is 29.
fgetss -- Read a line from the file pointer and filter out HTML tags
$fp = fopen('file3.txt','w');
$outStr = "my name is anllin";
fwrite($fp,$outStr,strlen($outStr));
fclose($fp);
$ ftp = fopen('file3.txt','r');
echo fgetss($ftp);
fclose($ftp);
?>
Output
my name is anllin
fread -- read file (safe for binary files)
$filename = 'file1.txt';
$fp = fopen($filename,'r');
$contents = fread($fp,filesize ($filename));
echo $contents;
fclose($fp);
?>
Output
my name is anllin, my age is 29 .
fpassthru -- Output all remaining data at the file pointer
php
$filename = 'file1.txt';
$fp = fopen($filename,'rb');
$leftSize = fpassthru($fp);
echo $leftSize;
fclose($fp);
?>
output
my name is anllin, my age is 29. 33
file -- Read the entire file into an array In
$lines = file('file1.txt' );
foreach ($lines as $line_num => $line)
{
echo $line_num.' : '.$line.'
';
}
?>
output
0 : my name is anllin,
1 : my age is 29.
readfile -- Output a file
$size = readfile('file1.txt');
echo $size;
?>
output
my name is anllin, my age is 29.33
file_get_contents -- Read the entire file into a string (new in php5.0)
$contents = file_get_contents('file1.txt');
echo $contents;
?>
output
my name is anllin, my age is 29.
feof -- test whether the file pointer reaches the end of the file Location
$fp = fopen('file1.txt' ,'r');
while(!feof($fp))
{
echo fgetc($fp);
}
fclose($fp);
?> ;
output
my name is anllin, my age is 29.
file_exists -- Check whether the file or directory exists
< ;?php
$filename = 'file1.txt';
if(file_exists($filename))
{
echo 'Perform file read and write operations';
}
else
{
echo 'The file you are looking for does not exist';
}
?>
output
Perform file read and write operations
filesize -- Get the file size
$file_size = filesize(' file1.txt');
echo $file_size;
?>
output
33
unlink -- 删除文件
$isDeleted = unlink('file3.txt');
echo $isDeleted;
?>
output
1
rewind -- 倒回文件指针的位置
ftell -- 返回文件指针读/写的位置
fseek -- 在文件指针中定位
$fp = fopen ( 'file1.txt', 'r' );
fgetc ( $fp );
fgetc ( $fp );
echo ftell ( $fp ) . '
';
rewind ( $fp );
echo ftell ( $fp ) . '
';
fgetc ( $fp );
fgetc ( $fp );
echo ftell ( $fp ) . '
';
fseek($fp,0);//same as rewind ($fp)
echo ftell ( $fp ) . '
';
?>
output
2
0
2
0
Flock的操作值
操作值 |
意义 |
LOCK_SH(以前为1) |
读写锁定。这意味着文件可以共享,其他人可以读该文件 |
LOCK_EX(以前为2) |
写操作锁定。这是互斥的,该文件不能被共享 |
LOCK_UN(以前为3) |
释放已有的锁定 |
LOCK_NB(以前为4) |
防止在请求加锁时发生阻塞 |
$filename = 'file1.txt';
$fp = fopen($filename,'rb');
flock($fp,LOCK_EX);//locked
$contents = fread($fp,filesize($ filename));
flock($fp,LOCK_UN);//unlocked
echo $contents;
fclose($fp);
?>
output
my name is anllin, my age is 29.
Directory handle operations
opendir -- open the directory handle
readdir -- read entries from the directory handle
closedir -- close the directory handle
$dir= opendir('../Basic6' );
while(!!$file = readdir($dir))
{
echo $file.'
';
}
closedir($dir) ;
?>
output
.
..
.buildpath
.project
.settings
demo1.php
demo10.php
demo11.php
demo12.php
demo13.php
demo14.php
demo15.php
demo16.php
demo17.php
demo18. php
demo19.php
demo2.php
demo20.php
demo3.php
demo4.php
demo5.php
demo6.php
demo7.php
demo8.php
demo9.php
file1.txt
file2.txt
scandir -- List files and directories in the specified path
$files = scandir('../Basic6');
foreach($files as $file )
{
echo $file.'
';
}
?>
output
.
..
.buildpath
.project
.settings
demo1.php
demo10.php
demo11.php
demo12.php
demo13.php
demo14.php
demo15.php
demo16.php
demo17.php
demo18.php
demo19.php
demo2.php
demo20.php
demo21.php
demo3.php
demo4.php
demo5.php
demo6.php
demo7.php
demo8.php
demo9.php
file1.txt
file2. txt
rename -- Rename a file or directory
rename('demo1.php','demo01.php');
if(file_exists('demo01.php'))
{
echo 'file rename success';
}
else
{
echo 'file rename fail';
}
?>
output
file rename success
rmdir -- Delete Directory
rmdir('123');
if(file_exists('123'))
{
echo 'delete file fail';
}
{
echo 'delete file success';
}
?> ;
output
delete file success

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